Apparatus for actuating a plurality of valves of piston-operated internal combustion engines

ABSTRACT

An apparatus for actuating valves for effecting a change in the charge of a piston machine, especially piston-operated internal combustion engine, in which the valve control is effected by yoke means controlling two valves, and in which the guiding means for the yoke means are laterally offset with regard to the area of engagement of said yoke means by the yoke-actuating means.

United States Patent Inventors Appl. No. Filed Patented Assignee Priority APPARATUS FOR ACTUATING A PLURALITY OF VALVES OF PISTON-OPERATED INTERNAL COMBUSTION ENGINES 7 Claims, 3 Drawing Figs.

U.S. Cl l23/90.22, 123/75 B Int. Cl F0111/26, F011 1/18 Field of Search 123/90.22,

References Cited UNITED STATES PATENTS 1,121,245 12/1914 Herkt 123/90 1,714,806 5/1929 Nutt 123/90 1,842,426 l/1932 Salisbury 123/90 2,070,926 2/1937 Sander et a1. 123/90 2,385,959 10/1945 Yingling 123/90 3,045,655 7/1962 Formia 123/188 X 3,331,359 7/1967 Skatsche 123/75 B 3,400,693 911968 Siding 123/90 X FOREIGN PATENTS 1,007,502 2/1952 France 123/90 A 380,688 9/1932 Great Britain t 123/90 A 833,319 4/1960 Great Britain 123/90 A 362,423 8/1938 ltaly 123/90 A Primary Examiner-Al Lawrence Smith Attorney-Walter Becker by the yoke-actuating means.

APPARATUS FOR ACTUATING A PLURALITY F VALVES OF PISTON-OPERATED INTERNAL COMBUSTION ENGINES The present invention relates to a device for actuating valves for controlling the charge and discharge of a piston machine, especially a piston-operated internal combustion engine in which two valves are actuated by means of a guiding yoke.

In order to make sure that with piston-operated internal combustion engines having a high speed a sufficiently large valve opening cross section is available for changing the charge, it is customary for reason of limited space to provide the cylinder head with a plurality of inlet and outlet valves. Such valves are as a rule arranged in pairs and are actuated simultaneously by corresponding actuating elements.

It is known for instance from the periodical Diesel and Gas Turbine Progress, March issue, 1968, pages 54-55, to effect the simultaneous actuation of valves arranged in pairs by means of a yoke member which is guided between the valves, said yoke member being guided in the area of the center of the forces. The yoke is actuated by a rocker whose point of attack on the yoke is located in the extension of the guiding means for the yoke.

The above arrangement has the drawback that the overall height for the yoke-guiding means and the overall height of the rocker and the cam shaft add up and considerably increase the overall size of the cylinder unit.

It is, therefore, an object of the present invention to reduce the overall volume of the cylinder unit by a corresponding design and arrangement of the yoke.

This object and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 diagrammatically illustrates a cross section through the cylinder head of a four-stroke cycle internal combustion engine.

FIG. 2 is a top view of the cylinder head after removal of the hood.

FIG. 3-is a section taken along the line III-III of FIG. I.

The arrangement according to the present invention is characterized primarily in that the guiding means for the yoke are laterally offset with regard to the point of attack of the rocker on the yoke. The lateral yoke-guiding means is advantageously placed on the outside with regard to the longitudinal central axis of the cylinder in order to keep the space between the valves free for the arrangement of the injection noule or the ignition device.

If the point of attack on the yoke is, in conformity with a further development of the invention, located at the power center, the yoke-guiding means are theoretically relieved from forces and moments.

According to a further development of the invention, it is suggested that the point of attack of the rocker on the yoke is located between the confining plane of the yoke arms on the valve side and the plane of support for the valve springs in the cylinder head. Such an arrangement results in an extremely low overall height of the cylinder unit without making the yoke-guiding means unduly short.

It may furthermore be advantageous with a device according to the invention which comprises a rocker, to arrange the rocker on the same side as the yoke-guiding means and to pass the rocker below an arm of the yoke between a valve and the yoke-guiding means. In this way, the rocker can, while taking full advantage of the space, be favorably arranged also when the yoke-guiding means in view of the assembly of the injection nozzle or the ignition device has to be placed on the outside.

In order to prevent the yoke from slipping off the valve shanks, it is suggested to secure the yoke against turning by means of the yoke-guiding means. This may for instance be effected by means of keys, sliding blocks or guiding means of suitable profile.

Referring now to the drawings in detail, the arrangement shown therein comprises a cylinder head 1 having arranged therein two outlet and two inlet valves 2 and 3, respectively.

The inlet valves are arranged in pairs and so are the oufit valves. The said pairs of valves are located in planes 4 and 5, respectively, transverse to the plane of symmetry 17 between the valve 2 on one hand and the valve 3 on the other hand. Both pairs of valves 2 and 3 are actuated through the intervention of push rods 6 and 7, rockers 8 and 9 and yokes l0 and II by means of a cam shaft not illustrated in the drawings and acting directly or indirectly upon the push rods 6 and 7. The special feature of the valve drive according to the invention consists in that the yoke 10, 11 is guided on a bolt 12 which is located in the point of attack of the forces laterally adjacent the plane 4, 5 respectively. The point of attack 14, 15 of the rockers 8, 9 on the yoke 10, I1 is so selected that the rocker is passed below the yoke arm and between the confining plane of A a yoke arm on the valve side and the plane of support 16 for the valve spring in the cylinder head.

FIGS. 2 and 3 also show the injection nozzle 17.

The point of attack l4, 15 of the rocker on the yoke is also indicated in FIG. 3.

The arrangement of the rocker on the same side as the yoke guiding means is particularly clearly shown in FIG. 2 where the rockers extend close to the outside of the cylinder head.

The yokes are guided and prevented from turning by the triangular profile of the yoke guiding means I2 and 13. The same result may, of course, also be obtained by a key and groove arrangement. a

It is, of course, to be understood that the present invention is, by no means, limited to the particular showing in the drawings but also comprises any modifications within the scope of the appended claims.

What we claim is:

1. In combination with an engine, especially internal combustion engine, having a cylinder head with a plurality of valves arranged in pairs, yoke means respectively associated with said pairs of valves and operable to control the same, guiding means guiding said yoke means along a plane forming the plane of symmetry for the valves of said pairs of valves to be controlled by the respective yoke means, and lever means operable to have one end portion thereof engage said yoke means for actuating the same to control the pertaining valve pair, said guiding means being laterally offset with regard to the area of engagement of said yoke means by said one end portion of said lever means.

2. An arrangement according to claim I, in which the area of engagement of said yoke means by said lever end portion is located at the center point of the valve-actuating forces.

3. An arrangement according to claim 1, in which said guiding means is located outwardly with regard to the longitudinal central axis of the cylinder pertaining to said valve pairs to be controlled by said yoke means.

4. An arrangement according to claim I, which includes spring means associated with said valves and having one end thereof resting on a portion of said cylinder head, and in which the area of engagement of said yoke means by said lever end portion is located between the plane defined by that surface of said yoke means which faces the pertaining valves and the plane defined by that portion of said cylinder head on which said one end of said spring means rests.

5. An arrangement according to claim I, in which said lever means is formed by rocker lever means arranged at the same side as said yoke guiding means with regard to the plane defined by the axes of the pertaining valve means, said rocker lever means having said one end portion thereof which is operable to engage said yoke means extend below an arm of said rocker lever means between said guiding means and one of said valves of the pertaining pair of valves.

6. An arrangement according to claim I, which includes means for preventing said yoke means from turning relative to said guiding means.

7. An arrangement according to claim 6, in which said guiding means is fixedly arranged in said cylinder head, and which includes groove and key means associated with said guiding .means for preventing said yoke means from turning relative to said guiding means. 

1. In combination with an engine, especially internal combustion engine, having a cylinder head with a plurality of valves arranged in pairs, yoke means respectively associated with said pairs of valves and operable to control the same, guiding means guiding said yoke means along a plane forming the plane of symmetry for the valves of said pairs of valves to be controlled by the respective yoke means, and lever means operable to have one end portion thereof engage said yoke means for actuating the same to control the pertaining valve pair, said guiding means being laterally offset with regard to the area of engagement of said yoke means by said one end portion of said lever means.
 2. An arrangement according to claim 1, in which the area of engagement of said yoke means by said lever end portion is located at the center point of the valve-actuating forces.
 3. An arrangement according to claim 1, in which said guiding means is locatEd outwardly with regard to the longitudinal central axis of the cylinder pertaining to said valve pairs to be controlled by said yoke means.
 4. An arrangement according to claim 1, which includes spring means associated with said valves and having one end thereof resting on a portion of said cylinder head, and in which the area of engagement of said yoke means by said lever end portion is located between the plane defined by that surface of said yoke means which faces the pertaining valves and the plane defined by that portion of said cylinder head on which said one end of said spring means rests.
 5. An arrangement according to claim 1, in which said lever means is formed by rocker lever means arranged at the same side as said yoke guiding means with regard to the plane defined by the axes of the pertaining valve means, said rocker lever means having said one end portion thereof which is operable to engage said yoke means extend below an arm of said rocker lever means between said guiding means and one of said valves of the pertaining pair of valves.
 6. An arrangement according to claim 1, which includes means for preventing said yoke means from turning relative to said guiding means.
 7. An arrangement according to claim 6, in which said guiding means is fixedly arranged in said cylinder head, and which includes groove and key means associated with said guiding means for preventing said yoke means from turning relative to said guiding means. 